Why Was Postage Due, PPC UK To Usa?

Hi,

I have this picture post card sent from the UK to the US. It appears that sufficient GB postage was affixed, though they do not appear canceled. 1d in total in stamps are present which was equal to the then UPU rate for post cards.

Apparently once in the US, the hand stamp "Forwarded upon receipt of postage due, (NYPOID)" was added and a 1¢ Washington-Franklin was added. There appears to be two different hand cancels on the cover. The first applied is from Madison Sq Station in NYC dated August 15. There is a second, and the date appears to be August 18, but to my eye, I think I see a New York at the top of the CDS. This would have been prior to arrival in Vermont. The stamp is applied over the red/pink "forwarded upon receipt" hand stamp.

The card itself has a printed statement that it was "For Inland Postage only'. Was this type of card ineligible for overseas use? How/why was the US postage added in NYC and not upon receipt by recipient in Vermont?

Help here better understanding this PPC would be appreciated,

Thanks,

Larry

In 1909 the international postcard rate was 2 cents from the U.S. 1 cent within country.

The "inland postage only" possibly reflects the fact that it took time for a divided back with message to be accepted by all postal authorities.